Document feeder

ABSTRACT

A document feeder includes a rotating head for moving individual documents from a stack of documents to document receiving rollers. Four vacuum ports are formed in the head at spaced points about its periphery. The ports are connected to apertures positioned in a circle on the bottom of the head. A duct extends from a vacuum source to a point adjacent the circle. As the head rotates, the apertures cooperate with the duct to connect each port to the vacuum source during the movement of the port between the stack of documents and the rollers.

0 United States Patent 1191 1111 3,738,641 Noah 1 June 12, 1973 DOCUMENT FEEDER 3,279,788 10/1966 Shields 271/44 A 2, 33, 4 l9 6 M d [75.] Inventor: Edward Dallas 3,379,782 10/1926 Sh i elds 2717/ 2 2 981,411 4/1961 Azari 271/27 X [73] Ass1gnee. Recognition Equipment 1 Incorporated, Dallas, Tu 1,766,482 6/1930 Broadmeyer 271 27 [22] Filed: 1971 Primary Examiner-Richard E. Aegerter 211 App] 174,20 Assistant Examiner-Bruce H. Stoner, Jr.

Att' -R'hd,H'&I-1bbd Related U.S. Application Data Omey at S ams u M [63] Continuation of Ser. No. 846,746, Aug. 1, 1969,

abandoned ABSTRACT A document feeder includes a rotating head for moving [52] U.S.Cl ..271/94,27l/26E individual documents from a Stack of documents to [51] IuL-Cl B65h 3/10 document receiving rollem Foul. vacuum ports are Fleld of Search E, 26, formed i the head at Spaced points about its p p y I 2.71/28 The ports are connected to apertures positioned in a circle on the bottom of the head. A duct extends from [56] References. C'ted a vacuum source to a point adjacent the circle. As the UNITED STAT S PATENTS head rotates, the apertures cooperate with the duct to 1,429,095 9/1922 Peters et a1. 271/27 Connect each port to the vacuum source during the 1,707,209 3/1929 Broadmeyer.... 271/27 movement of the port between the stack of documents 3,041,067 6/1962 Fux et a1 271/27 and the rollers, 3,260,520 7/1966 Sugden 271/34 X 2,033,849 3/1936 Mudd 271/29 4 Claims, 4 Drawing Figures 24 f O 4 I 38 42 34 3o Is I \\o 8 28 24 G 0 36 e w W 6 e y 2 44 /0'-| 1 PATENIED I 2 3.738.641

sum 1 OF 3 W %28 24 g g 36 '6" T W 40 32 F I2) 20 \F "3H" 1 MMMH 4k I FIG! IINVENTOR: EDWARD L. NOAH ATTORNEY PAIENIEDJUHIZIBB 3.738.641

I SHEEI 2 BF 3 INVENTOR: I EDWARD L. NOAH I PM VIM/951M ATTORNEY PATENIED JUN 1 2 I913 EDWARD NOAH DOCUMENT FEEDER This application is a continuation of application Ser. No. 846,746, filed Aug. 1, 1969, and now abandoned.

BACKGROUND OF THE INVENTION US. Pat. No. 3,300,207 granted to Childs et al. on Jan. 24, 1967 and US. Pat. No. 3,421,753 granted to Staples on Jan. 14, 1969 both relate to document feeders in which a stack of documents is pushed toward a feeding position by a document advancing paddle. At the feeding position, individual documents from the stack are moved into engagement with cooperating pairsof rollers. The rollers operate to transport the documents of the feeder.

In both the Childs and Staples devices, individual documents are moved from the stack to the rollers by a feeder plate that is reciprocated back and forth from the stack to the rollers. The feeder plate is provided with a plurality of vacuum ports that are connected to a vacuum source as the plate moves toward therollers and that is disconnected from the source as the plate moves away from the rollers. This secures individual documents to the feeder plate for movement from the stack to the rollers and releases documents from the plate when the documents are engaged with the rollers.

This invention relates to a document feeder that is similar to the Childs and Staples devices in that it in- SUMMARY OF THE INVENTION In the preferred'embodiment, this invention comprises a document feeder including vacuum ports mounted for sequential movement between two points to move individual documents therebetween. Preferably, the ports are formed in a head that rotates the ports between a stack of documents and a pair of cooperating rollers.

DESCRIPTION OF THE DRAWINGS A more complete understanding of the invention may be had by referring to the following Detailed Description when taken in conjunction with the drawings wherein:

FIG. 1 is a top view of a document feeder employing i the invention;

FIG. 2 is a sectional view taken generally along the the line 2-2 in FIG. 1;

FIG. 3 is an enlarged front viewof the face plate of the device shown in FIG. 1 in which certain parts have been broken away, and

FIG. 4 is an enlarged top view of a portion of the device shown in FIG. 1 in which certain parts are illustrated schematically.

DETAILED DESCRIPTION Referring now to the drawings and particularly to FIG. 1 thereof, there is shown a rotary head document feeder employing the invention. The feeder 10 includes a document advancing paddle 12 which operates to push a stack of documents over an upwardly extending bottom support plate 14 toward a face plate 16. The paddle 12 is slidably supported on a guide rod 18 and is driven toward the face plate 16 by a chain 20. The chain 20 is in turn driven by a motor (not shown) the operation of which is governed by a control system (also not shown). The control system operates the motor in such a way that the paddle 12 continuously urges the uppermost document of the stack into engagement with the face plate 16.

At the face plate 16, the documents in the stack are engaged in succession by a drum shaped head 22 which rotates through the face plate 16. The head 22 includes four vacuum ports 24 and operates to move individual documents from the stack to a document transport mechanism 26. A vacuum operated separator 28 posi tioned opposite the face plate 16 prevents the head 22 from moving more than one document at a time from the stack to the transport mechanism 26.

The transport mechanism 26 includes cooperating pairs of rollers 30 and 32 which receive documents from the head 22, cooperating pairs of idler rollers 34 and 36 and cooperating document transporting belts 38 and 40. The belts 38 and 40 are continuously driven by suitable motors (not shown) and operate to transport individual documents from the feeder 10 to a remote point. The rollers 30 are continuously rotated by a pair of belts 42 that are in turn driven by the belt 38. Similarly, the rollers 36 are driven by the belt 40.

The rollers 32 are reciprocated into and out of engagement with the rollers 30 by an eccentric 44 which operates in sychronism with the rotation of thehead 22. In use, the eccentric 44 moves the rollers 32 toward the rollers 30 each time a document is moved from the stack toward the transport mechanism 26 by the head 22. The rollers 30 and 32 cooperate to move the document into engagement with the belts 38 and 40 which in turn transports the document out of the feeder 10.

As is most clearly shown in FIG. 3, the head 22 rotates through an aperture 46 formed in the face plate 16. Each vacuum port 24 of the head 22 comprises a plurality of horizontally extending slots 48 formed in the head 22 and a layer of friction material 50 formed on the head 22 adjacent the slots 48. Rotation of the head 22 in the aperture 46 operates to move the ports 24 between a point near the center of the face plate 16 and a point adjacent the rollers 30 of the transport assembly 26.

The rollers 30 rotate in apertures 52 formed in the face plate 16. Similarly, the idler rollers 34 rotate in aperture 54. The rollers 30 are fixed to a pair of shafts 56 that are rotatably supported at the top and bottom of the face plate 16. The belts 42 extend around the shafts.

56 and around a shaft 58. The shaft 58 is pivotally supported and has a roller 60 secured to its mid portion. The belt 38 normally passes around the roller 60 and, accordingly, as the belt 38 is driven by its motor (not shown) the motion of the belt rotates the rollers 30 through the shaft 58, the belts 42 and the shafts 56.

Referring now to FIGS. 2 and 4, the structural details of the drum shaped head 22 are shown. Each of the vacuum ports 24 of the head 22 is connected to one of a plurality of passageways 62 formed in the head 22. Each of the passageways 62 extends from one of the ports 24 to one of a plurality of holes 64 formed in the bottom of the head 22. As is best shown in FIG. 4, the

holes 64 are positioned in a ring about the axis of rotation of the head 22.

Referring now to FIG. 2, a vacuum source 66 is connected to a collar 68 through a stop feed valve 70 and a vacuum duct 72. Whenever the valve 70 is opened, the vacuum of the source 66 is connected to the collar 68 through the duct 72. The collar 68 is preferably formed from a wear resistant material such as polytetrafluoroethylene and is urged into engagement with the bottom of the head 22 by a spring 74 positioned between the collar 68 and the bottom plate 14 of the document feeder 10.

As is best shown in FIG. 4, the collar 68 has an enlarged opening 76 formed in it. The opening 76 is connected to the vacuum duct 72 through a hole 78. The opening 76 cooperates with the holes 64 formed in the bottom of the head 22 to apply the vacuum of the source 66 to the ports 24 in sequence as the ports 24 are rotated through the aperture 46 in the face plate 16 by the head 22.

In use, a stack of documents is urged toward the face plate 16 by the paddle 12. The head 22 rotates each port 24 into engagement ,with the stack in sequence. The opening 76 and the holes 64 are so constructed and positioned that each port 24 is connected to the vacuum source 66 as it engages the uppermost document of the stack and is disconnected from the source 66 and vented to the atmosphere when it has transported the uppermost document into engagement with the rollers 30 and 32 of the transport mechanism 26. By this means, the feeder operates to sequentially move documents from thestack into engagement with the transport mechanism 26 which in turn moves the documents out of the feeder 10.

The document feeder illustrated in the drawing differs from prior document feeder in that the movement of the vacuum ports is entirely rotary, rather than reciprocatory, in nature. Also, the valving of the vacuum ports differs from prior devices in that it depends entirely upon the size and positioning of cooperating openings, rather than on the interaction of moving valving members. The device illustrated has been operated satisfactorily to move documents from a stack of documents into a transport mechanism at a rate of 3,200 documents per minute. Of course, because the head has four vacuum ports, during such an operation the head rotates at 800 rpm.

Although only one embodiment of the invention is illustrated in the accompanying drawings and described herein, it will be understood that the invention is not limited to the embodiment disclosed but is capable of rearrangement, modification, and substitution of parts and elements without departing from the spirit of the invention.

What is claimed is:

1. In a document feeder of the type including face and bottom plates, a paddle for pushing a stack of documents over the bottom plate toward the face plate, and a pair of rollers positioned adjacent the face plate for transporting individual documents out of the periphery to define a vacuum port, each of said slots extending parallel to the end surface and a substantial distance circumferentially around the drum so that said vacuum port comprises a substantial portion of the periphery of the drum at least a portion of the remainder of the periphery of the drum being imperforate so as to define a nonvacuum port area;

a layer of friction material formed on the portion of the periphery of the drum comprising the vacuum port;

means for rotating the drum through the face plate and aboutan axis displaced from the hole so that.

the vacuum port travels along a line extending between a point adjacent the stack and a point adjacent the rollers and so that the hole travels in a circle about the axis;

a polytetrafluoroethylene collar biased into engagement with the end surface of the drum and having an aperture formed in it in the path of travel of the hole in the drum;

a duct extending to the collar; and

means for maintaining a vacuum in the duct and thereby simultaneously establishing a vacuum in the entire lengths of the slots comprising the vacuum port whenever the hole in the drum is in alignment with the aperture of the collar and simultaneously releasing vacuum from the entire lengths of the slots comprising the vacuum port whenever the hole in the drum is out of alignment with the aperture of the collar.

2. In a document feeder of the type including face and bottom plates, a paddle for pushing a stack of documents over the bottom plate toward the face plate, and a pair of rollers positioned adjacent the face plate for transporting individual documents out of the feeder, an improved mechanism for moving individual documents from the stack to the rollers comprising:

a cylindrical drum having an axis and having at least two closed passageways extending through it from holes formed in one of its ends at points equidistance from its axis to sets of axially spaced slots formed in circumferentially spaced segments of the periphery of the drum and each extending a substantial distance circumferentially around the drum to define a pair of vacuum ports each comprising a substantial segment of the periphery of the drum;

said vacuum ports being separated by imperforate portions of the periphery of the drum each comprising a substantial portion thereof;

means for rotating the drum about its axis and through the face plate so that the vacuum ports se quentially travel along a line extending between a point adjacent the stack and a point adjacent the rollers and so that the holes travel in a circular path, and

means for maintaining a vacuum at a predetermined point in the circular path and thereby establishing a vacuum within each passageway during the travel of its vacuum port between the point adjacent the stack and the point adjacent the rollers,

whereby vacuum is simultaneously established throughout the entire lengths of the slots comprising each vacuum port as the corresponding hole comes into alignment with the vacuum maintaining means and is simultaneously released from the entire lengths of the slots comprising each vacuum 2 wherein the vacuum maintaining means comprises a polytetrafluoroethylene collar having an aperture formed in it, means biasing the collar into engagement with one end of the drum at the predetermined point in the circular path, a duct extending to the collar, and

means for maintaining a vacuum in the duct.

6 i= =l =l= 

1. In a document feeder of the type including face and bottom plates, a paddle for pushing a stack of documents over the bottom plate toward the face plate, and a pair of rollers positioned adjacent the face plate for transporting individual documents out of the feeder, an improved mechanism for moving individual documents from the stack to the rollers comprising: a drum including a flat end surface and a circular periphery extending axially from the end surface and having a closed passageway formed through it from a hole in the end surface to a plurality of circumferentially extending slots formed in a segment of the periphery to define a vacuum port, each of said slots extending parallel to the end surface and a substantial distance circumferentially around the drum so that said vacuum port comprises a substantial portion of the periphery of the drum at least a portion of the remainder of the periphery of the drum being imperforate so as to define a non-vacuum port area; a layer of friction material formed on the portion of the periphery of the drum comprising the vacuum port; means for rotating the drum through the face plate and about an axis displaced from the hole so that the vacuum port travels along a line extending between a point adjacent the stack and a point adjacent the rollers and so that the hole travels in a circle about the axis; a polytetrafluoroethylene collar biased into engagement with the end surface of the drum and having an aperture formed in it in the path of travel of thE hole in the drum; a duct extending to the collar; and means for maintaining a vacuum in the duct and thereby simultaneously establishing a vacuum in the entire lengths of the slots comprising the vacuum port whenever the hole in the drum is in alignment with the aperture of the collar and simultaneously releasing vacuum from the entire lengths of the slots comprising the vacuum port whenever the hole in the drum is out of alignment with the aperture of the collar.
 2. In a document feeder of the type including face and bottom plates, a paddle for pushing a stack of documents over the bottom plate toward the face plate, and a pair of rollers positioned adjacent the face plate for transporting individual documents out of the feeder, an improved mechanism for moving individual documents from the stack to the rollers comprising: a cylindrical drum having an axis and having at least two closed passageways extending through it from holes formed in one of its ends at points equidistance from its axis to sets of axially spaced slots formed in circumferentially spaced segments of the periphery of the drum and each extending a substantial distance circumferentially around the drum to define a pair of vacuum ports each comprising a substantial segment of the periphery of the drum; said vacuum ports being separated by imperforate portions of the periphery of the drum each comprising a substantial portion thereof; means for rotating the drum about its axis and through the face plate so that the vacuum ports sequentially travel along a line extending between a point adjacent the stack and a point adjacent the rollers and so that the holes travel in a circular path, and means for maintaining a vacuum at a predetermined point in the circular path and thereby establishing a vacuum within each passageway during the travel of its vacuum port between the point adjacent the stack and the point adjacent the rollers, whereby vacuum is simultaneously established throughout the entire lengths of the slots comprising each vacuum port as the corresponding hole comes into alignment with the vacuum maintaining means and is simultaneously released from the entire lengths of the slots comprising each vacuum port as the corresponding hole comes out of alignment with the vacuum maintaining means.
 3. The improved document feeder according to claim 2 further characterized by layers of friction material formed on the segments of the periphery of the drum comprising the vacuum ports.
 4. The improved document feeder according to claim 2 wherein the vacuum maintaining means comprises a polytetrafluoroethylene collar having an aperture formed in it, means biasing the collar into engagement with one end of the drum at the predetermined point in the circular path, a duct extending to the collar, and means for maintaining a vacuum in the duct. 